The invention relates to a display device preferably for motor vehicles for measured values, trouble indications and the like comprising at least one liquid crystal cell, illuminated from the rear to have areas with different colorations of letters, symbols, or indications illuminated.
In a known display device of this type, areas of the liquid crystal cell with various coloring of the letters and symbols and the data to be displayed, respectively, are provided by color foils which are inserted between the liquid crystal cell and a transflector arranged behind the latter, so that a good coloration is achieved in bright ambient light as well as in darkness (Elektronik, 1983, 19, page 16). In addition, it is also known to arrange a corresponding color imprint on the back of the LCD in the areas with different coloration when using transmissive LCDs. This is particularly desirable in large liquid crystal displays in motor vehicles where warning or trouble indications are to be emphasized over other indications, such as time, velocity, engine speed and the like, by different colors.
However, a disadvantage in the known solutions is that each area of the LCD can only have one color assigned to it. If different colors are desired in the various areas of the LCD, in each instance, in different types of vehicles it is necessary to have available a corresponding wide assortment of liquid crystal cells, which requires a considerable expenditure on storage. It is also disadvantageous that the different coloring produced by foils or color printing also affects the blocked areas of the LCD which are not being controlled, so that an unwanted background brightness varying in color and intensity results in these areas.